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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#354970#8325. 重塑时光skittles1412#40 1135ms3904kbC++179.2kb2024-03-16 10:00:432024-07-04 03:29:47

Judging History

你现在查看的是最新测评结果

  • [2024-07-04 03:29:47]
  • 评测
  • 测评结果:40
  • 用时:1135ms
  • 内存:3904kb
  • [2024-03-16 10:00:43]
  • 提交

answer

#include "bits/extc++.h"

using namespace std;

template <typename T, typename... U>
void dbgh(const T& t, const U&... u) {
    cerr << t;
    ((cerr << " | " << u), ...);
    cerr << endl;
}

#ifdef DEBUG
#define dbg(...)                                           \
    cerr << "L" << __LINE__ << " [" << #__VA_ARGS__ << "]" \
         << ": ";                                          \
    dbgh(__VA_ARGS__)
#else
#define cerr   \
    if (false) \
    cerr
#define dbg(...)
#endif

#define endl "\n"
#define long int64_t
#define sz(x) int(std::size(x))

template <typename T>
ostream& operator<<(ostream& out, const vector<T>& arr) {
    out << "[";
    for (int i = 0; i < sz(arr); i++) {
        if (i) {
            out << ", ";
        }
        out << arr[i];
    }
    return out << "]";
}

bool on(int mask, int bit) {
    return (mask >> bit) & 1;
}

struct mint {
    static constexpr int MOD = 1e9 + 7;

    static int norm(long x) {
        x %= MOD;
        if (x < 0) {
            x += MOD;
        }
        return x;
    }

    static mint pow(mint base, long exp) {
        mint ans = 1;

        while (exp) {
            if (exp & 1) {
                ans *= base;
            }
            base *= base;
            exp >>= 1;
        }

        return ans;
    }

    static mint inv(mint x) {
        return mint::pow(x, MOD - 2);
    }

    int x;

    mint() : x(0) {}
    mint(long x) : x(norm(x)) {}

    friend ostream& operator<<(ostream& out, const mint& m) {
        return out << m.x;
    }

    static mint from_unchecked(int x) {
        mint m;
        m.x = x;
        return m;
    }

    mint operator-() const {
        if (!x) {
            return {};
        }
        return mint::from_unchecked(MOD - x);
    }

    mint& operator+=(const mint& m) {
        x += m.x;
        if (x >= MOD) {
            x -= MOD;
        }
        return *this;
    }
    mint& operator-=(const mint& m) {
        return *this += -m;
    }

    mint& operator*=(const mint& m) {
        x = int(long(x) * m.x % MOD);
        return *this;
    }
    mint& operator/=(const mint& m) {
        return *this *= mint::inv(m);
    }

    friend mint operator+(mint a, const mint& b) {
        return a += b;
    }
    friend mint operator-(mint a, const mint& b) {
        return a -= b;
    }
    friend mint operator*(mint a, const mint& b) {
        return a *= b;
    }
    friend mint operator/(mint a, const mint& b) {
        return a /= b;
    }
};

struct Partition {
    static constexpr int MAXN = 17;

    vector<vector<int>> memo[MAXN][MAXN];

    vector<vector<int>> dp(int n, int m) {
        if (!n) {
            return {{}};
        } else if (n < m) {
            return {};
        }

        auto& ans = memo[n][m];

        if (sz(ans)) {
            return ans;
        }

        for (int i = m; i <= n; i++) {
            auto cur = dp(n - i, i);
            for (auto& a : cur) {
                a.insert(a.begin(), i);
            }

            ans.insert(ans.end(), begin(cur), end(cur));
        }

        return ans;
    }

    vector<vector<int>> solve(int n) {
        return dp(n, 1);
    }
} P;

struct M {
    static constexpr int MAXN = 100;

    mint fact[MAXN], ifact[MAXN];

    M() {
        fact[0] = ifact[0] = 1;
        for (int i = 1; i < MAXN; i++) {
            fact[i] = fact[i - 1] * i;
        }
        ifact[MAXN - 1] = mint::inv(fact[MAXN - 1]);
        for (int i = MAXN - 2; i >= 1; i--) {
            ifact[i] = (i + 1) * ifact[i + 1];
        }
    }

    mint choose(int n, int k) const {
        return fact[n] * ifact[k] * ifact[n - k];
    }

    mint choose2(int n, int k) const {
        if (n < 0 || k < 0 || k > n) {
            return 0;
        }
        return choose(n, k);
    }
} M;

namespace s1 {
bool solve(int, int, const vector<pair<int, int>>& edges) {
    if (!sz(edges)) {
        cout << 1 << endl;
        return true;
    }
    return false;
}
}  // namespace s1

namespace s2 {
bool solve(int n, int kv, const vector<pair<int, int>>& edges) {
    if (kv) {
        return false;
    }

    vector<int> graph[n];
    for (auto& [u, v] : edges) {
        graph[u].push_back(v);
    }

    mint dp[1 << n] {};
    dp[(1 << n) - 1] = 1;
    for (int mask = (1 << n) - 2; mask >= 0; mask--) {
        for (int i = 0; i < n; i++) {
            if (on(mask, i)) {
                continue;
            }

            bool bad = false;
            for (auto& v : graph[i]) {
                bad |= on(mask, v);
            }

            if (!bad) {
                dp[mask] += dp[mask | (1 << i)];
            }
        }
    }

    cout << dp[0] / M.fact[n] << endl;

    return true;
}
}  // namespace s2

namespace s3 {

constexpr int MAXN = 20;

vector<int> graph[MAXN];
int vis[MAXN];
bool has_cyc;

void dfs(int u) {
    if (vis[u]) {
        if (vis[u] == 1) {
            has_cyc = true;
        }
        return;
    }

    vis[u] = 1;
    for (auto& v : graph[u]) {
        dfs(v);
    }
    vis[u] = 2;
}

bool solve(int n, int kv, const vector<pair<int, int>>& edges) {
    if (n > 9) {
        return false;
    }

    mint ans = 0;

    for (auto& part : P.solve(n)) {
        int perm[n];
        iota(perm, perm + n, 0);

        do {
            int id[n];
            vector<int> bounds {0};

            for (auto& a : part) {
                int cl = bounds.back(), cr = cl + a;

                for (int i = cl; i < cr; i++) {
                    id[perm[i]] = sz(bounds) - 1;
                }

                bounds.push_back(cr);
            }

            bool bad = false;
            for (int i = 0; i < sz(part) - 1; i++) {
                bad |= part[i] == part[i + 1] &&
                       perm[bounds[i]] > perm[bounds[i + 1]];
            }
            if (bad) {
                continue;
            }

            fill(vis, vis + n, false);
            for (int i = 0; i < n; i++) {
                graph[i].clear();
            }

            has_cyc = false;

            int iperm[n];
            for (int i = 0; i < n; i++) {
                iperm[perm[i]] = i;
            }

            for (auto& [u, v] : edges) {
                if (id[u] == id[v]) {
                    has_cyc |= iperm[u] > iperm[v];
                    continue;
                }
                graph[id[u]].push_back(id[v]);
            }

            for (int i = 0; i < sz(part); i++) {
                dfs(i);
            }

            if (has_cyc) {
                continue;
            }

            int a = sz(part), ck = kv;
            mint cans = M.fact[a];
            ck -= a - 1;
            cans *= M.choose2(ck + a, a);
            ans += cans;
        } while (next_permutation(perm, perm + n));
    }

    cout << ans / (M.fact[n] * M.choose(n + kv, kv)) << endl;

    return true;
}
}  // namespace s3

namespace s4 {

bool solve(int n, int kv, const vector<pair<int, int>>& edges) {
    if (sz(edges) != n * (n - 1) / 2) {
        return false;
    }

    mint ans = 0;

    for (auto& part : P.solve(n)) {
        mint ways = M.fact[sz(part)];
        map<int, int> cnt;
        for (auto& a : part) {
            cnt[a]++;
        }
        for (auto& [_k, v] : cnt) {
            ways /= M.fact[v];
        }

        int a = sz(part), ck = kv;
        mint cans = ways * M.fact[a];
        ck -= a - 1;
        cans *= M.choose2(ck + a, a);
        ans += cans;
    }

    cout << ans / (M.fact[n] * M.choose(n + kv, kv)) << endl;

    return true;
}
}  // namespace s4

namespace s5 {

bool solve(int n, int kv, const vector<pair<int, int>>& edges) {
    if (sz(edges) != n - 1) {
        return false;
    }
    for (auto& [u, v] : edges) {
        if (u) {
            return false;
        }
    }

    mint ans = 0;

    for (auto& m_part : P.solve(n)) {
        for (int i = 0; i < sz(m_part); i++) {
            auto part = m_part;
            part[i]--;

            mint ways = M.fact[n - 1];
            map<int, int> cnt;
            for (auto& a : part) {
                cnt[a]++;
            }
            for (auto& [_k, v] : cnt) {
                ways /= M.fact[v];
            }

            int a = sz(part), ck = kv;
            mint cans = ways * M.fact[a];
            ck -= a - 1;
            cans *= M.choose2(ck + a, a);
            ans += cans;
        }
    }

    cout << ans / (M.fact[n] * M.choose(n + kv, kv)) << endl;

    return true;
}
}  // namespace s5

void solve() {
    int n, m, kv;
    cin >> n >> m >> kv;

    vector<pair<int, int>> edges(m);
    for (auto& [u, v] : edges) {
        cin >> u >> v;
        u--;
        v--;
    }

    bool solved = s1::solve(n, kv, edges) || s2::solve(n, kv, edges) ||
                  s3::solve(n, kv, edges) || s4::solve(n, kv, edges) ||
                  s5::solve(n, kv, edges);
    assert(solved);
}

int main() {
    cin.tie(nullptr);
    cin.exceptions(ios::failbit);
    ios_base::sync_with_stdio(false);
    solve();
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 5
Accepted
time: 0ms
memory: 3580kb

input:

3 2 0
1 2
1 3

output:

333333336

result:

ok single line: '333333336'

Test #2:

score: 5
Accepted
time: 1ms
memory: 3872kb

input:

5 7 5
1 4
2 3
1 2
4 5
2 5
2 4
1 5

output:

895039689

result:

ok single line: '895039689'

Test #3:

score: 0
Wrong Answer
time: 1ms
memory: 3624kb

input:

13 12 13
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13

output:

230969385

result:

wrong answer 1st lines differ - expected: '76923078', found: '230969385'

Test #4:

score: 0
Wrong Answer
time: 1ms
memory: 3736kb

input:

14 13 14
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
1 14

output:

407910392

result:

wrong answer 1st lines differ - expected: '535714290', found: '407910392'

Test #5:

score: 5
Accepted
time: 2ms
memory: 3640kb

input:

14 13 0
2 9
1 2
1 3
3 8
6 11
2 7
1 5
5 12
2 13
3 14
3 10
3 6
2 4

output:

700595243

result:

ok single line: '700595243'

Test #6:

score: 0
Runtime Error

input:

14 13 14
9 11
2 9
5 10
4 6
10 13
2 3
2 7
4 12
2 4
3 8
7 14
3 5
1 2

output:


result:


Test #7:

score: 5
Accepted
time: 0ms
memory: 3636kb

input:

13 0 13

output:

1

result:

ok single line: '1'

Test #8:

score: 5
Accepted
time: 1ms
memory: 3904kb

input:

14 91 14
3 4
2 10
3 10
1 13
6 8
5 6
10 13
7 8
4 9
4 7
3 7
13 14
2 12
1 3
6 9
9 14
1 10
2 9
7 11
9 11
3 12
8 10
4 13
5 9
11 12
5 14
8 12
8 13
5 13
1 5
6 11
9 13
2 5
1 14
7 14
4 14
3 5
5 11
6 12
1 2
7 10
1 4
1 8
6 10
3 8
6 13
10 14
7 12
10 11
2 13
8 11
11 13
6 7
10 12
3 14
4 5
1 6
2 14
5 10
8 14
4 8
1...

output:

4362623

result:

ok single line: '4362623'

Test #9:

score: 5
Accepted
time: 1135ms
memory: 3900kb

input:

9 15 9
1 2
3 5
2 8
4 8
1 4
2 5
2 7
4 5
1 9
6 8
6 9
1 3
3 7
5 9
5 8

output:

426526937

result:

ok single line: '426526937'

Test #10:

score: 5
Accepted
time: 1120ms
memory: 3820kb

input:

9 14 9
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
4 5
6 8
4 7
6 7
3 8
4 6

output:

214820829

result:

ok single line: '214820829'

Test #11:

score: 5
Accepted
time: 1ms
memory: 3668kb

input:

13 68 0
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
2 5
2 6
2 7
2 8
2 9
2 10
2 11
2 12
2 13
3 4
3 5
3 6
3 7
3 8
3 9
3 10
3 11
3 12
3 13
4 5
4 6
4 7
4 8
4 9
4 10
4 11
4 12
4 13
5 6
5 7
5 8
5 9
5 10
5 11
5 12
5 13
6 7
6 8
6 9
6 10
6 11
6 12
6 13
7 8
7 10
7 11
7 12
7 13
8 13
9 10
9 11
9 12
9 13...

output:

65784302

result:

ok single line: '65784302'

Test #12:

score: 0
Runtime Error

input:

13 39 13
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
3 4
3 5
3 6
3 7
3 8
3 9
3 10
3 11
3 12
3 13
4 8
4 9
4 10
4 12
4 13
5 6
5 7
5 10
5 11
5 13
6 7
6 11
6 13
8 9
8 12
8 13
11 13

output:


result:


Test #13:

score: 0
Runtime Error

input:

14 11 14
2 13
4 11
4 14
5 14
6 9
6 14
7 11
9 14
10 12
10 14
12 14

output:


result:


Test #14:

score: 0
Runtime Error

input:

14 46 14
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
1 14
2 9
2 10
2 11
2 13
2 14
3 4
3 6
3 10
3 11
3 12
3 13
3 14
4 6
4 10
4 11
4 12
4 13
4 14
5 7
5 8
5 9
5 11
5 13
5 14
7 8
7 9
7 14
10 11
10 13
10 14
11 13
11 14
13 14

output:


result:


Test #15:

score: 0
Runtime Error

input:

14 70 14
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
1 14
2 3
2 4
2 5
2 7
2 8
2 9
2 10
2 11
2 12
2 13
2 14
3 11
3 13
3 14
4 5
4 7
4 8
4 10
4 11
4 12
4 13
4 14
5 7
5 8
5 10
5 12
5 13
5 14
6 7
6 8
6 9
6 10
6 11
6 12
6 13
6 14
7 8
7 10
7 12
7 13
7 14
8 10
8 12
8 13
8 14
9 11
9 12
9 13
9 14
10 1...

output:


result:


Test #16:

score: 0
Runtime Error

input:

14 69 14
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
1 14
2 3
2 5
2 6
2 7
2 9
2 10
2 11
2 12
2 13
2 14
3 5
3 6
3 7
3 9
3 10
3 11
3 12
3 13
3 14
4 7
4 8
4 9
4 10
4 11
4 12
4 13
4 14
5 6
5 7
5 9
5 10
5 11
5 12
5 13
5 14
6 7
6 9
6 10
6 11
6 12
6 13
6 14
7 9
7 10
7 11
7 12
7 13
7 14
8 12
8 13
8 14
9 10
...

output:


result:


Test #17:

score: 0
Runtime Error

input:

14 15 14
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
1 14
4 6
5 9

output:


result:


Test #18:

score: 0
Runtime Error

input:

15 17 15
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
1 10
1 11
1 12
1 13
1 14
1 15
3 13
3 15
13 15

output:


result:


Test #19:

score: 0
Runtime Error

input:

15 17 15
1 2
1 3
1 4
1 5
1 6
1 7
1 12
1 15
7 12
7 15
8 15
9 15
10 15
11 15
12 15
13 15
14 15

output:


result:


Test #20:

score: 0
Runtime Error

input:

15 16 15
1 2
1 3
1 10
2 10
3 10
4 5
4 6
4 7
4 8
4 9
4 10
4 11
4 12
4 13
4 14
4 15

output:


result: